Aromatic CompoundsA molecular model of benzene, the reactions of bromine with cylohexane, cyclohexene, benzene, phenol, and toluene, the effect of substituents and number of methyl groups on the electron density of aromatic rings, and chlorination reactions of methyl benzenes are demonstrated.

Isolation of Curcumin from TurmericAndrew M. Anderson, Matthew S. Mitchell, and Ram S. MohanThe active ingredient in turmeric is curcumin, which is approximately 2% by weight of the root of turmeric. We have developed two simple procedures for isolation of curcumin from turmeric, making this a new and interesting natural product isolation experiment. Anderson, Andrew M.; Mitchell, Matthew S.; Mohan, Ram S. J. Chem. Educ.2000, 77, 359.

Coumarin, Naphthalene, and Additional Polycyclic Aromatic HydrocarbonsWilliam F. ColemanThe featured molecules this month are drawn from two papers. The first, "One-Pot Synthesis of 7-Hydroxy-3-carboxycoumarin in Water", is a Green Chemistry feature by Fringuelli, Piermatti, and Pizzo. The three-dimensional versions of the molecules in the synthesis of the coumarin derivative are directly tied to the reaction scheme included in the paper, opening the possibility of showing large numbers of complex synthetic pathways in this manner.The second paper is "Determining the Carbon-Carbon Distance in an Organic Molecule with a Ruler" by Simoni, Tubino, and Ricchi. This article describes an experiment to determine the size of a naphthalene molecule, using an extension of classic experiments for determining molecular size and Avogadro's number. While the structure of naphthalene will come as no surprise to most students, the molecule collection also includes additional polycyclic aromatic hydrocarbons (PAHs) that can be used to introduce students to the environmental and health issues related to these molecules.